Method of and machine for forming radiator elements



G. HORVATH 1,840,317

METHOD OF AND MACHINE FOR FORMING RADIATOR ELEMENTS Jan. 12, 1932.

Filed Nov. 5. 1927 I5 Sheets-Sheet Jan. 12, 1932. G HORVATH 1,840,317

METHOD OF AND MACHINE FOR FORMING RADIATOR ELEMENTS Filed MW. 5, 1927 5Sheets-Sheet 2 8 wuzmto'c E'eza Harmih WW Jan. 12, 1932. a. HORVATH1,340,317

I METHOD OF AND MACHINE FOR FORMING FADIATOR ELEMENTS Filed Nov. 5. 19275 Sheets-Sheet 3 lllllljllllll E'azaMrzraflz 4 I r/ I Patented lan. 12,1932 UNITED STATES GEZA HORVATH, OF HIGHLAND PARK, MICHIGAN METHOD OFAND MACHINE FOR FORMING RADIATOR ELEMENTS Application filed November 5,1927. Serial No. 231,364.

The present invention relates to the art of making radiator elements ofthe type wherein a ribbon is wound spirally on a tube, and is animprovement on my prior Patent No. 1,472,719, of October 30, 1923.

The principal object of the inventlon is to improve the contact betweenthe rlbbon and the coil, whereby the efficiency of the element isincreased. Incidently, the invention provides a-firmer engagementbetween the ribbon and the tube to such an extent that an auxiliarymeans such as solder need not be used in certain cases.

In present radiator elements of this general construction, the crimpingof the coil 1mparts a curvature thereto, but the radlus of thiscurvature is greater than the external radius of the tube andconsequently there is a tendency for the ribbon to unwind from the tube.This situation requires the use of solder as already indicated, and itis further necessary to employ dead soft metal in order to avoidresiliency which would further tend to draw the ribbon away from thecoil. S'uch soft metal is unsatisfactory because it easily becomesdamaged in shipping and handling.

These difficulties are overcome by the present invention according towhich the corrugaao tions are ironed out and the ribbon flattened alongone edge thereof. The curvature imparted to the metal by the crimpingoperation is considerably diminished by the ironing or pressingoperation, and the final curvature is such that the ribbon may be woundsnugly on the tube and adhere thereto without the use of solder. Thepressing operation is conducted in a manner to stretch the metal at theflattened edge, and this fact contributes to the reduction in the radiusof curvature of the ribbon. Also, spring metal may be used since thetendency of the ribbon to unwind from the tube is overcome. Theflattening of the ribbon along its convex edge permits a larger airspace and hence a greater air capacity between the convolutions than ifthe ribbon were corrugated from edge to edge.

The invention is fully disclosed by way of 7 example in the followingdescription and in the accompanying drawings, in which Figure 1 is anend View of the machine; Fig. 2 is a plan view thereof; Fig. 3 is a sideelevation; Fig. 4 is a detail perspective View of the ribbon after thecrimping operation;

Fig. 5 is a detail section through the pressing rolls;

Fig. 6 is an enlarged detail elevation of the crimping rolls; and v Fig.7 is a section on the line 7-7 of Figure 6.

Reference to these views will now be made by use of like characterswhich are employed to designate corresponding parts throughout.

On the frame 1 of the machine is mounted an upright bracket 2 havinglegs 3 and 4 secured upon the frame by bolts 5. At the upper end of thebracket are journaled a pair of juxtaposed guide rolls 6 and 7 slightlyspaced from each other in order to engage the faces of a ribbon 8 passedtherethrough. At the lower end of the bracket is mounted an arm 9 on apivot pin 10. This arm carries a rotatable crimping roll 11 consistingof a beveled toothed member as shown in ures 2 and 3. Adjacent the roll11, the bracket 2 is thickened at 12 to the extent of the width of thearm 9 in order that a similar crimping roll 13 pivoted to this portionwill mesh with the roll 11. A finger 14 extends from the arm 9 over thethickened portion 12 which further supports a pair of springs 15received in sockets 16 in the finger piece. These springs tend to drawthe roll 11 towards the roll 13, and the movement of the roll 11 islimited by a set screw 17 threaded therethrough and engaging thevertical wall of the thickened part 12. By means of this screw thespacing of the rolls 11 and 13 may be adjusted for various thicknessesof ribbon passed therethrough. After the ribbon has passed between therolls it is formed with transverse corrugations 18 which reduce in depthtowards one edge due to the beveled character of the rolls, as shown inFigure 4, whereby the ribbon is somewhat curved.

The frame 1 has a face 19 which slopes ed to engage the corrugate ribbon8 as it comes from the crimping rolls at the edge at which thecorrugations 18 are narrower. The

details of the pressing rolls will presently be described. v r

In a bearin 22 upon the frame 1 1s mounted one end 0 a shaft 23, theprolongation of which lies adjacent the rolls 21. A screw 24 is-splinedas at 25 upon the shaft 23 and is threaded through a nut 26 mounted uponthe frame 1. The outer end of the shaft carries a gear 27 by which it isdriven, and the inner end of the screw is equipped with a collar 28 intowhich one end of a tube 29 may be secured by a set screw 30. It will beap parent that the ironing or pressing action of the rolls 21 upon theribbon tend to form the latter into a helix, the axis of which coincidessubstantially with the axis of the tube 29, so that the ribbon is-woundupon the tube as it is delivered from the crimping rolls. P

Upon the frame is mounted another block 31 carrying a pair of pressingrolls 32 similar to the members 21 for engaging the flattened ed e ofthe ribbon at another point.

ince both pressing units are identical, a detailed description of onlyone will be necessary. The block is formed with slots or gecesses 33 and34 in which are pivotally mounted arms 35 and 36 respectively whichcarry the pressing rolls. The block has a further recess 37 incommunication with the slot 34 for receiving one end of a spring 38.Through the lower end of the arm 36 is threaded a screw 39 carrying adisk 40 engaging the remainin end of the spring. This arrangement ten sto move the pressing roll carried by the arm 36 into engagement with theribbon, and the tension of the spring may be regulated by the screw 39.The lower end of'the other arm 35 carries a set screw 41 engageable withthe central part of the block, thereby limiting the outward movement ofthe remaining roll against the roll under spring pressure, and furtherproviding a means for adjusting the final position of the arm 35 androll carried thereby. The peripheries of the rolls are formed each withtwo surfaces 42 and 43 angularly disposed to each other as clearly shownin Figure 5.

I The surfaces 42 come into firm contact with a portion (if the ribbonat opposite sides thereof along one edge and press the corru- 1spartlcularly desirable in automobile work.

gations out of the ribbon at this region. Further, the adjustment of thepresser rolls is*such that the surfaces 42 will engage the ribbon withsuflicient pressure to reduce the thickness thereof as shown in Figure 5and thereby stretch the same. This stretching of the metal, which isapproximately twentyeight percent, along one edge causes the ribbon tocoil, and the adjustment of the parts is such that the ribbon willsnugly engage the outer wall of the tube 29. The corrugations to beretained at the other end are accommodated in the space between theanularly disposed faces 43. The presser rolls urther temper .or' hardenthe metal while ironing the same.

It is preferred to perform the pressing and stretching operation in twostages at the rolls 21'and 32, as this second stage reduces the radiusof curvature to such an extent that the ribbon binds tightly on thetube. In fact, the ribbon is so tight on the tube that it leaves a markthereon. This is decidedly superior to the; results obtained accordingto my previous patent identified above, wherein the coiled ribbon has atendency to unwind from the tube when the product is placed in thesolderin bath. In the present instance solder is a so used between theribbon and the tube but rimarily to fill the air spaces. It is neverteless possible to use but a single pair of rolls properly adjusted forthe purose.

As will be understood, the initial transverse crimping of the ribbon'ischanged by the action of rolls 21, the latter serving to reduce thedepth of the crimps of the previously applied fin, the rolls acting onthe outer or peripheral zone of such fin. The initial crimping thusproduces what may be considered as an embryo fin formation which isapplied to the tube in such embryo stage of development, and thenailixed by the succeeding action of rolls 32.

The tube 29 is moved on its own axis and axially of the coiled ribbon bythe action of the screw 24 in the nut 26. If the initial end of theribbon is attached to the forward end of the tube as at 44, the axialmovement of the tube is suflicient to draw the ribbon through theseveral pairs of rollers without the use of an auxiliary feeding device.

The process of the invention may be performed on a lathe or any machinefor feeding or turning the tube, or simply by turning the tube andfeeding the ribbon lengthwise, it being understood that the inventionresides principally in the flattening of the ribbon at one edge andretaining the corrugations in the other edge.

It will now be apparent that the several alleged advantages of theinvention are made possible by the method and means described herein. Itmight be added that the absence of solder for securing the ribbon to thetube Although a specific embodiment of the invention has beenillustrated and described, it will be understood that variousalterations in the details of construction may be made without departingfrom the scope of the invention as indicated by the appended claims.

What I claim is: i I 1. A method of applying metallic ribbon on a tubeto form a radiator element, which other roll varies transversely of saidrolls, and consists in crimping the ribbon transversely a pair ofopposed ressing rolls under presthroughout its width to produce a spiralemsure against each ot er and adapted to receive bryo fin formationappliable about the tube between them one edge of a ribbon which hasspirally, locating the embryo formation in be predetermined positionsspirally on the tube, and aflixing the embryo formation to the tube byreducing the crimp depth of the peripheral zone of the positionedformation by pressure application to the opposite faces of the fin insuch zone.

2. A method of forming radiator elements consisting in crimping a ribbontransversely by producing transverse corrugations therein of diminishingdepth from one edge of the ribbon to the other, whereby to form aconcave edge where the corrugations are deeper and a convex edge wherethe corrugations are shallower, winding said ribbon on a tube, andpressing out the corrugations at the shallower ends thereof.

3. A method of forming radiator elements consisting in crimping a ribbontransversely by producing transverse corrugations therein of diminishingdepth from one edge of the ribbon to the other, whereby to form aconcave edge where the corrugations are deeper and a convex edge wherethe corrugations are shallower, pressing out the corrugations at theshallower ends thereof, winding said ribbon on a tube and stretching theribbon at the shallower ends of the corrugations while pressing out thelatter.

4. In a machine for forming radiator elements, a crimping means formetallic ribbon, said means being adapted to provide a spirallike ribbonformation, means for positioning the formation about a tube, and meansincluding a pair of opposed pressure rolls relatively yieldable andoperative on the positioned formation to reduce the crimp depth of theperipheral zone of the formation and thereby tighten the positionedformation to the tube.

5. In a machine for forming radiator elements, a pair of meshed, toothedrolls arranged so that the extent of penetration of the teeth of oneroll between those of the other roll varies transversely of said rolls,and means for stretching one edge of a ribbon which has been passedbetwr en said toothed rol s.

6. In a machine for forming radiator elements, a pair of bevelled,toothed crimping rolls arranged in mesh and with corresponding facesparallel, whereby the extent of penetration of the teeth of one rollbetween those of the other roll varies transversely of said rolls, andmeans for stretching one edge of a ribbon which has been passed betweensaid crimping rolls. V

7. In a machine for forming radiator elements, a pair of meshed, toothedrolls arranged so that the extent of penetration of the teeth of oneroll between those of the en passed between said toothed rolls. Intestimony whereof I afiix my si ature.

GEZA HORV TH.

